2-Usa "!" asi: stackoverflow.com/questions/4542732/how-do-i-negate-a-test-with-regular-expressions-in-a-bash-script
Código
3-tambien podrias usar ":" en el true del if sin cambiar nada mas del codigo
if [[ ! $TARGET =~ $REPLY ]];then
stackoverflow.com/questions/3224878/what-is-the-purpose-of-the-colon-gnu-bash-builtin